| 摘要 |
PURPOSE:The titled resin composition excellent in transparency, weather resistance and moldability as well as impact resistance, solvent resistance and clouding resistance, consisting of the first rigid layer, the second soft layer and the third rigid layer in which the MW is decreasing from the inside to the outside. CONSTITUTION:The titled composition is obtained as follows. Methyl methacrylate (MMA) and, if necessary, other monomers are emulsion-polymerized to form the first layer, Tg >=25 deg.C. In the presence of the first layer, alkyl acrylate (AA), 0.1-5wt% polyfunctional grafting agent and, if necessary, other monomers and a polyfunctional crosslinking agent are emulsion-polymerized to form the second layer, Tg <=25 deg.C. Next, in the presence of the particles consisting of said first and second layers, MMA and, if necessary, other monomers are emulsion- polymerized, while the amount of a chain transfer agent added is increased gradually from the initial small amount, whereby the third layer in which the MW is decreasing gradually from the inside to the outside is formed.
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